Email from the command line, done right.

Mailfire sends plain-text, Markdown, and HTML email from scripts, cron jobs, CI pipelines, and your terminal — through Mailgun, Gmail, or any SMTP server. Beautiful templates, attachments, retries, and JSON output included.

Get started GitHub

A single binary for Linux, macOS, and Windows. Open source, MIT licensed.

$ mailfire --md --to ops@example.com --subject "Nightly backup" <<EOF
# Backup finished

All **12 hosts** completed in 4m 31s.

> [!WARNING]
> files01 needed a second attempt.
EOF
<20261018T091500.3ad5358f96c70a25@example.com>

Everything a notification needs

Markdown that looks great

Write Markdown or HTML and Mailfire renders it into a responsive template that works in Outlook, dark mode, and on mobile — with a plain-text alternative.

Markdown, alerts, and images

Three ways to send

Use the Mailgun API, your Gmail account with send-only OAuth, or standard SMTP submission to any provider or local relay.

SMTP

Never lose a message

Network errors and outages defer the message instead of dropping it. mailfire resend retries with backoff from cron.

Deferred delivery

No alert storms

Opt-in deduplication sends a repeated monitoring alert once per cooldown, across sends and retries.

Notification deduplication

Built for scripts

Stable exit codes, one JSON document per command, and environment-only configuration for CI and containers.

Scripting and automation

Preview before you send

Render the exact HTML body to a file without credentials or network access, and iterate on templates offline.

Local preview

Four templates, or your own

card, card-serif, plain, and plain-serif cover reports, alerts, and newsletters. Export them, edit the HTML and CSS, and Mailfire inlines the styles so every client renders them the same.

See the templates

The four built-in email templates: card, card-serif, plain, and plain-serif

Install in seconds

brew tap thorstenkramm/tap
brew trust --cask thorstenkramm/tap/mailfire
brew install --cask mailfire

Installation

# Add the signed, pinned repository first (see the Linux guide), then:
sudo apt install mailfire

Linux package repositories

# Add the signed repository first (see the Linux guide), then:
sudo dnf install mailfire